Thermosetting hyperbranched compositions and methods for use thereof

ABSTRACT

Hyperbranched polymers and methods for preparing the same are disclosed. The polymers are obtained based on monomers synthesized via reacting a substituted or unsubstituted cyclic anhydride with a bifunctional amine.

RELATED APPLICATIONS

This application claims the benefit of priority under 35 USC §119 ofU.S. Provisional Applications Ser. No. 61/088,578 filed Aug. 13, 2008,the entire disclosure of which is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to thermosetting adhesive compositions anduses therefor. In particular, the present invention relates tothermosetting compounds and compositions containing curablehyperbranched compounds.

BACKGROUND OF THE INVENTION

Adhesive compositions, particularly conductive adhesives, are used for avariety of purposes in the fabrication and assembly of semiconductorpackages and microelectronic devices. The more prominent uses includebonding of electronic elements such as integrated circuit chips to leadframes or other substrates, and bonding of circuit packages orassemblies to printed wire boards. Adhesives useful for electronicpackaging applications typically exhibit properties such as goodmechanical strength, curing properties that do not affect the componentor the carrier, and thixotropic properties compatible with applicationto microelectronic and semiconductor components.

SUMMARY OF THE INVENTION

The present invention relates to hyperbranched polymers and methods forpreparing the same. Specifically, the invention provides methods forpreparing a monomer, comprising reacting a substituted or unsubstitutedcyclic anhydride with a bifunctional amine according to the reactionScheme A:

where X is absent or is selected from the group consisting of acycloaliphatic, an aromatic, or a heteroaromatic moiety forming acondensed ring system with the furan ring of compound I; Y is absent oris selected from the group consisting of a C₁-C₁₅ alkyl or a C₂-C₁₅alkylene moiety; and each of R₁ and R₂ is a moiety comprising a reactivefunctional group independently selected from the group consisting ofhydroxyl, carboxyl, vinyl, allyl, acrylate, and methacrylate, therebyobtaining the monomer II.

In certain embodiments, X is absent. I other embodiments, X iscyclohexane or benzene. In one aspect of the invention, Y is a C₂-C₁₅alkylene moiety. In another aspect, Y is a C₂-C₁₅ alkylene moietydodecenyl group.

The cyclic anhydride can, for example, be succinic anhydride,isobenzofuran dione, hexahydro isobenzofuran dione, or a derivativethereof. In certain embodiments, the cyclic anhydride isdodecenylsuccinic anhydride. The bifunctional amine can, for example, bediethanolamine, dibutanolamine, or diallylamine.

The present invention further provides methods for preparing ahyperbranched polymer, comprising reacting the monomer II of Scheme Awith a compound having a functionality selected from the groupconsisting of hydroxyl and carboxyl. Monomers and hyperbranched polymersobtained the methods of the invention are also provided.

Exemplary monomers provide by the invention include Compounds 1-4, 5, 6,11 and 12 described herein below.

The present invention also provides methods for increasing toughness ofan adhesive composition, by incorporating into the composition ahyperbranched polymer of the invention.

The present invention also provides compositions that include at leastone monomer or hyperbranched polymer described herein. In certainembodiments, the composition is an adhesive composition, which may becured or uncured. Adhesive compositions of the invention may include acuring initiator, coupling agent, and/or filler. In certain embodiments,the adhesive compositions of the invention also include a chain-extendedbismaleimide and/or at least one compound selected from the groupconsisting of an epoxy, an oxetane, a phenol, a phenyl acetate, anacrylate, a methacrylate, a maleimide, a vinyl ether, a vinyl ester, astyrenic compound and an allyl functional compound.

DETAILED DESCRIPTION

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory onlyand are not restrictive of the invention claimed. As used herein, theuse of the singular includes the plural unless specifically statedotherwise. As used herein, “or” means “and/or” unless stated otherwise.Furthermore, use of the term “including” as well as other forms, such as“includes,” and “included,” is not limiting.

The section headings used herein are for organizational purposes onlyand are not to be construed as limiting the subject matter described.

Unless specific definitions are provided, the nomenclatures utilized inconnection with, and the laboratory procedures and techniques ofanalytical chemistry, synthetic organic and inorganic chemistrydescribed herein are those known in the art, such as those set forth in“IUPAC Compendium of Chemical Terminology: IUPAC Recommendations (TheGold Book)” (McNaught ed.; International Union of Pure and AppliedChemistry, 2^(nd) Ed., 1997) and “Compendium of Polymer Terminology andNomenclature: IUPAC Recommendations 2008” (Jones et al., eds;International Union of Pure and Applied Chemistry, 2009). Standardchemical symbols are used interchangeably with the full namesrepresented by such symbols. Thus, for example, the terms “hydrogen” and“H” are understood to have identical meaning. Standard techniques may beused for chemical syntheses, chemical analyses, and formulation.

DEFINITIONS

“About” as used herein means that a number referred to as “about”comprises the recited number plus or minus 1-10% of that recited number.For example, “about” 100 degrees can mean 95-105 degrees or as few as99-101 degrees depending on the situation. Whenever it appears herein, anumerical range such as “1 to 20” refers to each integer in the givenrange; e.g., “1 to 20 carbon atoms” means that an alkyl group cancontain only 1 carbon atom, 2 carbon atoms, 3 carbon atoms, etc., up toand including 20 carbon atoms (although the term “alkyl” also includesinstances where no numerical range of carbon atoms is designated).

“Adhesive” or “adhesive compound” as used herein, refers to anysubstance that can adhere or bond two items together. Implicit in thedefinition of an “adhesive composition” or “adhesive formulation” is thefact that the composition or formulation is a combination or mixture ofmore than one species, component or compound, which can include adhesivemonomers, oligomers, and/or polymers along with other materials, whereasan “adhesive compound” refers to a single species, such as an adhesivepolymer or oligomer.

More specifically, adhesive composition refers to un-cured mixtures inwhich the individual components in the mixture retain the chemical andphysical characteristics of the original individual components of whichthe mixture is made. Adhesive compositions are typically malleable andmay be liquids, paste, gel or another form that can be applied to anitem so that it can be bonded to another item.

“Cured adhesive,” “cured adhesive composition” or “cured adhesivecompound” refers to adhesives components and mixtures obtained fromreactive curable original compound(s) or mixture(s) thereof which haveundergone a chemical and/or physical changes such that the originalcompound(s) or mixture(s) is (are) transformed into a solid,substantially non-flowing material. A typical curing process may involvecrosslinking.

“Curable” means that an original compound(s) or composition material(s)can be transformed into a solid, substantially non-flowing material bymeans of chemical reaction, crosslinking, radiation crosslinking, or thelike. Thus, adhesive compositions of the invention are curable, butunless otherwise specified, the original compound(s) or compositionmaterial(s) is (are) not cured.

“Thermoplastic,” as used herein, refers to the ability of a compound,composition or other material (e.g. a plastic) to dissolve in a suitablesolvent or to melt to a liquid when heated and freeze to a solid, oftenbrittle and glassy, state when cooled sufficiently.

“Thermoset,” as used herein, refers to the ability of a compound,composition or other material to irreversibly “cure” resulting in asingle tridimensional network that has greater strength and lesssolubility compared to the non-cured product. Thermoset materials aretypically polymers that may be cured, for example, through heat (e.g.above 200° Celsius), via a chemical reaction (e.g. epoxy ring opening,free-radical cure, etc.), or through irradiation (e.g. visible light,U.V., or X-ray irradiation).

Thermoset materials, such as thermoset polymers or resins, are typicallyliquid or malleable forms prior to curing, and therefore may be moldedor shaped into their final form, and/or used as adhesives. Curingtransforms the thermoset resin into a rigid infusible and insolublesolid or rubber by a cross-linking process. Thus, energy and/orcatalysts are typically added that cause the molecular chains to reactat chemically active sites (unsaturated or epoxy sites, for example),linking the polymer chains into a rigid, 3-D structure. Thecross-linking process forms molecules with a higher molecular weight andresultant higher melting point. During the reaction, when the molecularweight of the polymer has increased to a point such that the meltingpoint is higher than the surrounding ambient temperature, the polymerbecomes a solid material.

“Cross-linking,” as used herein, refers to the attachment of two or moreoligomer or longer polymer chains by bridges of an element, a moleculargroup, a compound, or another oligomer or polymer. Crosslinking may takeplace upon heating; some crosslinking processes may also occur at roomtemperature or a lower temperature. As cross-linking density isincreased, the properties of a material can be changed fromthermoplastic to thermosetting.

As used herein, “B-stageable” refers to the properties of an adhesivehaving a first solid phase followed by a tacky rubbery stage at elevatedtemperature, followed by yet another solid phase at an even highertemperature. The transition from the tacky rubbery stage to the secondsolid phase is thermosetting. However, prior to thermosetting, thematerial behaves similarly to a thermoplastic material. Thus, suchadhesives allows for low lamination temperatures while providing highthermal stability.

A “die” as used herein, refers to a small block of semiconductingmaterial, on which a functional circuit is fabricated.

The term “monomer” refers to a molecule which can undergo polymerizationor copolymerization thereby contributing constitutional units to theessential structure of a macromolecule (a polymer).

“Polymer” and “polymer compound” are used interchangeably herein, torefer generally to the combined the products of a single chemicalpolymerization reaction. Polymers are produced by combining monomersubunits into a covalently bonded chain. Polymers that contain only asingle type of monomer are known as “homopolymers,” while polymerscontaining a mixture of monomers are known as “copolymers.”

The term “copolymers” is inclusive of products that are obtained bycopolymerization of two monomer species, those obtained from threemonomers species (terpolymers), those obtained from four monomersspecies (quaterpolymers), etc. It is well known in the art thatcopolymers synthesized by chemical methods include, but are not limitedto, molecules with the following types of monomer arrangements:

alternating copolymers, which contain regularly alternating monomerresidues;

periodic copolymers, which have monomer residue types arranged in arepeating sequence;

random copolymers, which have a random sequence of monomer residuetypes;

statistical copolymers, which have monomer residues arranged accordingto a known statistical rule; and

block copolymers, which have two or more homopolymer subunits linked bycovalent bonds. The blocks of homopolymer within block copolymers, forexample, can be of any length and can be blocks of uniform or variablelength. Block copolymers with two or three distinct blocks are calleddiblock copolymers and triblock copolymers, respectively.

The skilled artisan will appreciate that a single copolymer molecule mayhave different regions along its length that can be characterized as analternating, periodic, random, etc. A copolymer product of a chemicalpolymerization reaction may contain individual polymeric fragments thateach differ in the arrangement of monomer units. The skilled artisanwill further be knowledgeable in methods for synthesizing each of thesetypes of copolymers, and for varying reaction conditions to favor onetype over another.

Furthermore, the length of a polymer chain according to the presentinvention, will typically vary over a range or average size produced bya particular reaction. The skilled artisan will be aware, for example,of methods for controlling the average length of a polymer chainproduced in a given reaction and also of methods for size-selectingpolymers after they have been synthesized.

Unless a more restrictive term is used, polymer is intended to encompasshomopolymers, and copolymers having any arrangement of monomer subunitsas well as copolymers containing individual molecules having more thanone arrangement. With respect to length, unless otherwise indicated, anylength limitations recited for the polymers described herein are to beconsidered averages of the lengths of the individual molecules inpolymer.

As used herein, “oligomer” or “oligomeric” refers to a polymer having afinite and moderate number of repeating monomers structural units.Oligomers of the invention typically have 2 to about 100 repeatingmonomer units; frequently 2 to about 30 repeating monomer units; andoften 2 to about 10 repeating monomer units; and usually have amolecular weight up to about 3,000.

The skilled artisan will appreciate that oligomers and polymers may,depending on the availability of polymerizable groups or side chains,subsequently be incorporated as monomers in further polymerization orcrosslinking reactions.

As used herein, “aliphatic” refers to any alkyl, alkenyl, cycloalkyl, orcycloalkenyl moiety.

As used herein, “alkyl” refers to straight or branched chain hydrocarbylgroups having from 1 up to about 500 carbon atoms. The terms “alkyl” and“substituted alkyl” include, respectively, substituted and unsubstitutedC₁-C₅₀₀ straight chain saturated aliphatic hydrocarbon groups,substituted and unsubstituted C₂-C₂₀₀ straight chain unsaturatedaliphatic hydrocarbon groups, substituted and unsubstituted C₄-C₁₀₀branched saturated aliphatic hydrocarbon groups, substituted andunsubstituted C₁-C₅₀₀ branched unsaturated aliphatic hydrocarbon groups.

For example, the definition of “alkyl” includes but is not limited to:methyl (Me), ethyl (Et), propyl (Pr), butyl (Bu), pentyl, hexyl, heptyl,octyl, nonyl, decyl, undecyl, ethenyl, propenyl, butenyl, penentyl,hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, isopropyl(i-Pr), isobutyl (i-Bu), tert-butyl (t-Bu), sec-butyl (s-Bu), isopentyl,neopentyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl,cycloheptyl, cyclooctyl, cyclopentenyl, cyclohexenyl, cycloheptenyl,cyclooctenyl, methylcyclopropyl, ethylcyclohexenyl, butenylcyclopentyl,adamantyl, norbornyl and the like.

“Substituted alkyl” refers to alkyl moieties bearing substituents thatinclude but are not limited to alkyl, alkenyl, alkynyl, hydroxy, oxo,alkoxy, mercapto, cycloalkyl, substituted cycloalkyl, heterocyclic,substituted heterocyclic, aryl, substituted aryl (e.g., arylC₁₋₁₀alkylor arylC₁₋₁₀alkyloxy), heteroaryl, substituted heteroaryl (e.g.,heteroarylC₁₋₁₀alkyl), aryloxy, substituted aryloxy, halogen, haloalkyl(e.g., trihalomethyl), cyano, nitro, nitrone, amino, amido, carbamoyl,═O, ═CH—, —C(O)H, —C(O)O—, —C(O)—, —S—, —S(O)₂—, —OC(O)—O—, —NR—C(O)—,NR—C(O)—NR—, —OC(O)—NR—, where R is H or lower alkyl, acyl, oxyacyl,carboxyl, carbamate, sulfonyl, sulfonamide, sulfuryl, C₁₋₁₀alkylthio,arylC₁₋₁₀alkylthio, C₁₋₁₀alkylamino, arylC₁₋₁₀alkylamino,N-aryl-N—C₁₋₁₀alkylamino, C₁₋₁₀alkyl carbonyl, arylC₁₋₁₀alkylcarbonyl,C₁₋₁₀alkylcarboxy, aryl C₁₋₁₀alkylcarboxy, C₁₋₁₀alkyl carbonylamino,aryl C₁₋₁₀alkylcarbonylamino, tetrahydrofuryl, morpholinyl, piperazinyl,and hydroxypyronyl.

As used herein, “cycloalkyl” refers to cyclic ring-containing groupscontaining in the range of about 3 up to about 20 carbon atoms,typically 3 to about 15 carbon atoms. In certain embodiments, cycloalkylgroups have in the range of about 4 up to about 12 carbon atoms, and inyet further embodiments, cycloalkyl groups have in the range of about 5up to about 8 carbon atoms. and “substituted cycloalkyl” refers tocycloalkyl groups further bearing one or more substituents as set forthbelow.

As used herein, “alkenyl,” “alkene” or “olefin” refers to straight orbranched chain unsaturated hydrocarbyl groups having at least onecarbon-carbon double bond, and having in the range of about 2 up to 500carbon atoms. In certain embodiments, alkenyl groups have in the rangeof about 5 up to about 250 carbon atoms, and in yet further embodiments,cycloalkyl groups have in the range of about 10 up to about 100 carbonatoms. “Substituted alkenyl” refers to alkenyl groups further bearingone or more substituents as set forth above.

As used herein, “alkynyl” refers to straight or branched chainhydrocarbyl groups having at least one carbon-carbon triple bond, andhaving in the range of 2 up to about 100 carbon atoms, typically about 4to about 50 carbon atoms, and frequently about 8 to about 25 carbonatoms. “Substituted alkynyl” refers to alkynyl groups further bearingone or more substituents as set forth below.

As used herein, the term “aryl” represents an unsubstituted, mono-, di-or trisubstituted monocyclic, polycyclic, biaryl aromatic groupscovalently attached at any ring position capable of forming a stablecovalent bond, certain preferred points of attachment being apparent tothose skilled in the art (e.g., 3-phenyl, 4-naphtyl and the like). Thearyl substituents are independently selected from the group consistingof halo, —OH, —SH, —CN, —NO₂, trihalomethyl, hydroxypyronyl, C₁₋₁₀alkyl,arylC₁₋₁₀alkyl, C₁₋₁₀alkyloxyC₁₋₁₀alkyl, arylC₁₋₁₀alkyloxyC₁₋₁₀alkyl,C₁₋₁₀alkylthioC₁₋₁₀alkyl, arylC₁₋₁₀alkylthioC₁₋₁₀alkyl,C₁₋₁₀alkylaminoC₁₋₁₀alkyl, arylC₁₋₁₀alkylaminoC₁₋₁₀alkyl,N-aryl-N—C₁₋₁₀alkylaminoC₁₋₁₀alkyl, C₁₋₁₀alkylcarbonylC₁₋₁₀alkyl, arylC₁₋₁₀alkylcarbonyl C₁₋₁₀alkyl, C₁₋₁₀alkylcarboxyC₁₋₁₀alkyl,arylC₁₋₁₀alkylcarboxyC₁₋₁₀alkyl, C₁₋₁₀alkylcarbonylaminoC₁₋₁₀alkyl, andarylC₁₋₁₀alkylcarbonylaminoC₁₋₁₀alkyl.

Some specific examples of moieties encompassed by the definition of“aryl” include but are not limited to phenyl, biphenyl, naphthyl,dihydronaphthyl, tetrahydronaphthyl, indenyl, indanyl, azulenyl,anthryl, phenanthryl, fluorenyl, pyrenyl and the like. “Substitutedaryl” refers to aryl groups further bearing one or more substituents asset forth below.

As used herein, “arylene” refers to a divalent aryl moiety. “Substitutedarylene” refers to arylene moieties bearing one or more substituents asset forth above.

As used herein, “alkylaryl” refers to alkyl-substituted aryl groups and“substituted alkylaryl” refers to alkylaryl groups further bearing oneor more substituents as set forth below.

As used herein, “arylalkyl” refers to aryl-substituted alkyl groups and“substituted arylalkyl” refers to arylalkyl groups further bearing oneor more substituents as set forth below. Some examples of included butare not limited to (4-hydroxyphenyl)ethyl, or (2-aminonaphthyl) hexenyl.

As used herein, “arylalkenyl” refers to aryl-substituted alkenyl groupsand “substituted arylalkenyl” refers to arylalkenyl groups furtherbearing one or more substituents as set forth below.

As used herein, “arylalkynyl” refers to aryl-substituted alkynyl groupsand “substituted arylalkynyl” refers to arylalkynyl groups furtherbearing one or more substituents as set forth below.

As used herein, “aroyl” refers to aryl-carbonyl species such as benzoyland “substituted aroyl” refers to aroyl groups further bearing one ormore substituents as set forth below.

As used herein, “hetero” refers to groups or moieties containing one ormore heteroatoms such as N, O, Si and S. Thus, for example“heterocyclic” refers to cyclic (i.e., ring-containing) groups havinge.g. N, O, Si or S as part of the ring structure, and having in therange of 3 up to 14 carbon atoms. “Heteroaryl” and “heteroalkyl”moieties are aryl and alkyl groups, respectively, containing e.g. N, O,Si or S as part of their structure. The terms “heteroaryl”,“heterocycle” or “heterocyclic” refer to a monovalent unsaturated grouphaving a single ring or multiple condensed rings, from 1 to 8 carbonatoms and from 1 to 4 hetero atoms selected from nitrogen, sulfur oroxygen within the ring.

The definition of heteroaryl includes but is not limited to thienyl,benzothienyl, isobenzothienyl, 2,3-dihydrobenzothienyl, furyl, pyranyl,benzofuranyl, isobenzofuranyl, 2,3-dihydrobenzofuranyl, pyrrolyl,pyrrolyl-2,5-dione, 3-pyrrolinyl, indolyl, isoindolyl, 3H-indolyl,indolinyl, indolizinyl, indazolyl, phthalimidyl (orisoindoly-1,3-dione), imidazolyl. 2H-imidazolinyl, benzimidazolyl,pyridyl, pyrazinyl, pyradazinyl, pyrimidinyl, triazinyl, quinolyl,isoquinolyl, 4H-quinolizinyl, cinnolinyl, phthalazinyl, quinazolinyl,quinoxalinyl, 1,8-naphthyridinyl, pteridinyl, carbazolyl, acridinyl,phenazinyl, phenothiazinyl, phenoxazinyl, chromanyl, benzodioxolyl,piperonyl, purinyl, pyrazolyl, triazolyl, tetrazolyl, thiazolyl,isothiazolyl, benzthiazolyl, oxazolyl, isoxazolyl, benzoxazolyl,oxadiazolyl, thiadiazolyl, pyrrolidinyl-2,5-dione,imidazolidinyl-2,4-dione, 2-thioxo-imidazolidinyl-4-one,imidazolidinyl-2,4-dithione, thiazolidinyl-2,4-dione,4-thioxo-thiazolidinyl-2-one, piperazinyl-2,5-dione,tetrahydro-pyridazinyl-3,6-dione,1,2-dihydro-[1,2,4,5]tetrazinyl-3,6-dione,[1,2,4,5]tetrazinanyl-3,6-dione, dihydro-pyrimidinyl-2,4-dione,pyrimidinyl-2,4,6-trione, 1H-pyrimidinyl-2,4-dione,5-iodo-1H-pyrimidinyl-2,4-dione, 5-chloro-1H-pyrimidinyl-2,4-dione,5-methyl-1H-pyrimidinyl-2,4-dione, 5-isopropyl-1H-pyrimidinyl-2,4-dione,5-propynyl-1H-pyrimidinyl-2,4-dione,5-trifluoromethyl-1H-pyrimidinyl-2,4-dione, 6-amino-9H-purinyl,2-amino-9H-purinyl, 4-amino-1H-pyrimidinyl-2-one,4-amino-5-fluoro-1H-pyrimidinyl-2-one,4-amino-5-methyl-1H-pyrimidinyl-2-one,2-amino-1,9-dihydro-purinyl-6-one, 1,9-dihydro-purinyl-6-one,1H-[1,2,4]triazolyl-3-carboxylic acid amide,2,6-diamino-N.sub.6-cyclopropyl-9H-purinyl,2-amino-6-(4-methoxyphenylsulfanyl)-9H-purinyl,5,6-dichloro-1H-benzoimidazolyl,2-isopropylamino-5,6-dichloro-1H-benzoimidazolyl,2-bromo-5,6-dichloro-1H-benzoimidazolyl, and the like. Furthermore, theterm “saturated heterocyclic” represents an unsubstituted, mono-, di- ortrisubstituted monocyclic, polycyclic saturated heterocyclic groupcovalently attached at any ring position capable of forming a stablecovalent bond, certain preferred points of attachment being apparent tothose skilled in the art (e.g., 1-piperidinyl, 4-piperazinyl and thelike).

Hetero-containing groups may also be substituted. For example,“substituted heterocyclic” refers to a ring-containing group having inthe range of 3 up to 14 carbon atoms that contains one or moreheteroatoms and also bears one or more substituents, as set forth above.Examples of substituents include, but are not limited to halo, —OH, —SH,—CN, —NO₂, trihalomethyl, hydroxypyronyl, C₁₋₁₀alkyl, arylC₁₋₁₀alkyl,C₁₋₁₀alkyloxyC₁₋₁₀alkyl, arylC₁₋₁₀alkyloxy C₁₋₁₀alkyl,C₁₋₁₀alkylthioC₁₋₁₀alkyl, arylC₁₋₁₀alkylthioC₁₋₁₀alkyl,C₁₋₁₀alkylaminoC₁₋₁₀alkyl, arylC₁₋₁₀alkylamino C₁₋₁₀alkyl,N-aryl-N—C₁₋₁₀alkylaminoC₁₋₁₀alkyl, C₁₋₁₀alkylcarbonylC₁₋₁₀alkyl,arylC₁₋₁₀alkylcarbonyl C₁₋₁₀alkyl, C₁₋₁₀alkylcarboxyC₁₋₁₀alkyl,arylC₁₋₁₀alkylcarboxyC₁₋₁₀alkyl C₁₋₁₀alkylcarbonylaminoC₁₋₁₀alkyl, andarylC₁₋₁₀alkylcarbonylamino C₁₋₁₀alkyl.

As used herein, the term “phenol” includes compounds having one or morephenolic functions per molecule. The terms aliphatic, cycloaliphatic andaromatic, when used to describe phenols, refers to phenols to whichaliphatic, cycloaliphatic and aromatic residues or combinations of thesebackbones are attached by direct bonding or ring fusion.

As used herein, “acyl” refers to alkyl-carbonyl species.

As used herein, the terms “halogen,” “halide,” or “halo” includefluorine, chlorine, bromine, and iodine.

“Allyl” as used herein, refers to refers to a compound bearing at leastone moiety having the structure:

“Imide” as used herein, refers to a functional group having two carbonylgroups bound to a primary amine or ammonia. The general formula of animide of the invention is:

“Polyimides” are polymers of imide-containing monomers. Polyimides aretypically linear or cyclic. Non-limiting examples of linear and cyclic(e.g. an aromatic heterocyclic polyimide) polyimides are shown below forillustrative purposes.

“Maleimide,” as used herein, refers to an N-substituted maleimide havingthe formula as shown below:

where R is an aromatic, herteroaromatic, aliphatic, or polymeric moiety.

“Bismaleimide” or “BMI”, as used herein, refers to a polyimide compoundin which two imide moieties are linked by a bridge, i.e., a compoundhaving the general structure shown below:

where R is an aromatic, herteroaromatic, aliphatic, or polymeric moiety.

BMIs can cure through an addition rather than a condensation reaction,thus avoiding problems resulting from the formation of volatiles. BMIscan be produced by a vinyl-type polymerization of a pre-polymerterminated with two maleimide groups.

As used herein, the term “acrylate” refers to a compound bearing atleast one moiety having the structure:

As used herein, the term “acrylamide” refers to a compound bearing atleast one moiety having the structure:

As used herein, the term “methacrylate” refers to a compound bearing atleast one moiety having the structure:

As used herein, the term “methacrylamide” refers to a compound bearingat least one moiety having the structure:

As used herein, the term “citraconimide” refers to a compound bearing atleast one moiety having the structure:

“Itaconate,” as used herein refers to a compound bearing at least onemoiety having the structure:

As used herein, “siloxane” refers to any compound containing a Si—Omoiety. In certain embodiments, siloxanes of the invention include 2 ormore repeating units of Si—O.

As used herein “epoxy” refers to a thermosetting epoxide polymer thatcures by polymerization and crosslinking when mixed with a catalyzingagent or “hardener,” also referred to as a “curing agent” or “curative.”Epoxies of the present invention include, but are not limited toaliphatic, cycloaliphatic, glycidyl ether, glycidyl ester, glycidylamine epoxies, and the like, and combinations thereof. Epoxies of theinvention include compounds bearing at least one oxirane group, i.e., amoiety having the structure:

As used herein, the term “oxetane” refers to a compound bearing at leastone moiety having the structure:

As used herein, the term “vinyl ether” refers to a compound bearing atleast one moiety having the structure:

As used herein, the term “vinyl ester” refers to a compound bearing atleast one moiety having the structure:

As used herein, “styrenic” refers to a compound bearing at least onemoiety having the structure:

“Oxazoline” as used herein, refers to a compound bearing at least onemoiety having the structure:

“Benzoxazine” as used herein, refers to a compound bearing at least onemoiety having the structure:

“Fumarate” as used herein, refers to a compound bearing at least onemoiety having the structure:

“Propargyl” as used herein, refers to a compound bearing at least onemoiety having the structure:

“Cyanate” as used herein, refers to a compound bearing at least onemoiety having the structure:

As used herein, “norbornyl” refers to a compound bearing at least onemoiety having the structure:

As used herein, the term “free radical initiator” refers to any chemicalspecies which, upon exposure to sufficient energy (e.g., light, heat, orthe like), decomposes into parts which are uncharged, but every one ofsuch part possesses at least one unpaired electron.

As used herein, the term “coupling agent” refers to chemical speciesthat are capable of bonding to a mineral surface and which also containpolymerizably reactive functional group(s) so as to enable interactionwith the adhesive composition. Coupling agents thus facilitate linkageof the die-attach paste to the substrate to which it is applied.

“Modulus” or “Young's modulus” as used herein, is a measure of thestiffness of a material. Within the limits of elasticity, modulus is theratio of the linear stress to the linear strain which can be determinedfrom the slope of a stress-strain curve created during tensile testing.

“Thixotropy” as used herein, refers to the property of a material whichenables it to stiffen or thicken in a relatively short time uponstanding, but upon agitation or manipulation to change to low-viscosityfluid; the longer the fluid undergoes shear stress, the lower itsviscosity. Thixotropic materials are therefore gel-like at rest butfluid when agitated and have high static shear strength and low dynamicshear strength, at the same time.

“Glass transition temperature” or “T_(g)” is used herein to refer to thetemperature at which an amorphous solid, such as a polymer, becomesbrittle on cooling, or soft on heating. More specifically, it defines apseudo second order phase transition in which a supercooled melt yields,on cooling, a glassy structure and properties similar to those ofcrystalline materials e.g. of an isotropic solid material.

“Thermogravimetric analysis” or “TGA” refers to a method of testing andanalyzing a material to determine changes in weight of a sample that isbeing heated in relation to change in temperature. “Decomposition onset”refers to a temperature when the loss of weight in response to theincrease of the temperature indicates that the sample is beginning todegrade.

The invention is based on the discovery that a certain hyperbranchedcompounds are useful as adhesives for the microelectonic packagingindustry. In particular, it has been discovered that the hyperbranchedcompounds of the invention increase toughness of an adhesive compositionin which they are incorporated. The compounds of this invention are alsouseful in a variety of other applications. Invention compounds can beused in automotive, marine, and aerospace coatings and adhesives. Theproperties of certain invention compounds make these compounds suitablefor use in dental matrix resins and adhesives. Invention compounds canalso be used as components of matrix resins for composites used insports equipment, automotive bodies, and boat construction. Thecompounds of this invention also have attractive properties for use inadhesives for diverse industrial applications such as thread-lockmaterials and building materials.

Thus, the invention provides hydrolytically stable hydrophobic productsthat are hyperbranched, and methods for obtaining such products.According to embodiments of the invention, to obtain the hyperbranchedproducts, a monomer is synthesized first. To obtain a monomer, abifunctional anhydride is reacted with a bifunctional amine. The monomeris then reacted with a suitable reactive compound to extend the chain,for example with a compound having hydroxyl, carboxyl or a similarfunctionality.

Those having ordinary skill in the art will be able to select suitableanhydride and amine to carry out the synthesis. Non-limiting examples ofa bifunctional anhydride that may be used include succinic anhydride,isobenzofuran dione, hexahydro isobenzofuran dione, and derivativesthereof, such as succinic anhydride substituted with a functionalmoiety. Such a functional moiety may be an alkenyl group; accordingly,an example of a suitable derivative of succinic anhydride that may beused is dodecenylsuccinic anhydride. Non-limiting examples of abifunctional amine that may be used include diethanolamine,dibutanolamine, and diallylamine.

In sum, a general synthetic process that may be used for obtaining amonomer may be illustrated by the reaction Scheme A:

In the general process illustrated by the reaction Scheme A, X is absentor is a cycloaliphatic, aromatic, or heteroaromatic moiety (e.g.,benzene or cyclohexane ring) that forms a condensed ring system with thefuran ring of the starting compound I. Y is absent or is a C₁-C₁₅ alkylor C₂-C₁₅ alkylene moiety, such as dodecenyl group. Each of R₁ and R₂is, independently, a group that includes a reactive functional group,such as hydroxyl, carboxyl, vinyl, allyl, acrylate, or methacrylate.Those having ordinary skill in the art may choose other reactivefunctional groups R₁ and R₂, if desired. The final product II of theprocess shown on Scheme A is a monomer that can be further used asdescribed below.

Examples of specific compounds that may be used as monomer II, accordingto the present invention include compounds 1-4 shown below:

Monomer represented as compound II on Scheme A is then subjected topolycondensation with another compound (a co-monomer) having a suitablereactive group, such as hydroxyl or carboxyl, to obtain thehyperbranched product of the present invention. Those having ordinaryskill in the art may choose the most appropriate co-monomer andconditions for carrying out such polycondensation, depending on thespecific nature of the co-monomer selected to be condensed with themonomer II. According to embodiments of the present invention,polycondensation may be carried out, for example, at a temperaturebetween about 130° C. and about 160° C., with or without catalyst.

One exemplary, non-limiting method of synthesizing a branched compoundis illustrated by the reaction Scheme B:

The process illustrated by Scheme B includes the reaction of theoriginal compound (1,3-dioxo-1,3-dihydroisobenzofuran-5-carbonylchloride) with a bifunctional amine (diethanolamine) to make a monomerand the condensation of the monomer with an alcohol(4,6,6-trimethyl-2-(2,4,4-trimethylpentyl)heptan-1-ol). The resultingproduct is a branched compound,2-(bis(2-hydroxyethyl)carbamoyl)-5-((4,6,6-trimethyl-2-(2,4,4-trimethylpentyl)heptyloxy)carbonyl)benzoicacid.

Examples of specific hyperbranched polymers made according toembodiments of the present invention include polymers 5-12 shown below:

The invention also provides for monomers prepared according to processsimilar to that shown by Scheme A and/or hyperbranched compoundsprepared according to process similar to that shown by Scheme B to beused in adhesive compositions containing the chain-extendedbismaleimide. Such adhesive compositions can include at least one of anepoxy, an oxetane, a phenol, a phenyl acetate, an acrylate, amethacrylate, a maleimide, a vinyl ether, a vinyl ester, a styreniccompound or an allyl functional compound.

Compositions Containing Hyperbranched Polymers and Monomers

The present invention provides compositions, such as adhesives,containing at least one hyperbranched monomer and/or polymer of theinvention. For example, the hyperbranched compound may be usedindependently as an adhesive or may be combined with other materials andreagents to prepare adhesive compositions. In certain embodiments, thehyperbranched compound of the invention may be combined with otheradhesives and/or resins to prepare adhesive compositions. Ahyperbranched compound of the invention may be used as the sole monomerof an adhesive composition of the invention. In other embodiments, thehyperbranched compound of the invention may be combined with othermonomers, such as thermoset monomers, to make a fully formulatedadhesive composition. In certain embodiments, invention hyperbranchedcompounds can be used as co-monomers in a Diels-Alder type cure.

In certain embodiments of the invention, a hyperbranched compound asdescribed above is present in a composition, such as an adhesivecomposition, in an amount from 0.5 weight percent (wt %) to about 98 wt%, based on the total weight of the composition. Typically, thecomposition will contain an amount of the compound equal to at leastabout 5 wt %, often at least about 10 wt %, frequently at least about 20wt %, and in some embodiments at least about 40 wt % based on the totalweight of the composition.

In another embodiment of the invention, the composition containing thehyperbranched compound of the invention includes at least oneco-monomer, which is typically present in an amount from 10 wt % toabout 90 wt %, based on the total weight of the composition. In someaspects of the invention, the composition will contain an amount of theco-monomer equal to at least about 15 wt %, often at least about 20 wt%, frequently at least about 25 wt %, and in some embodiments at leastabout 30 wt % based on the total weight of the composition. Co-monomerssuitable for use in the hyperbranched compound-containing compositionsaccording to the invention include, but are not limited to, acrylates,acrylamides, methacrylates, methacrylamides, cyanate esters, maleimides,vinyl ethers, vinyl esters, styrenic compounds, allyl functionalcompounds, and olefins.

In still other embodiments, the present invention provides adhesivecompositions that are die-attach pastes which include 5 weight percentto about 85 weight percent (wt %) of at least one hyperbranchedcompounds described herein, based on total weight of the composition; 10wt % to about 90 wt % of at least one maleimide, bismaleimide, orpolymaleimide, based on the total weight of the composition; 0 weightpercent to about 60 weight percent of a compound selected fromacrylates, methacrylates, acrylamides, methacrylamides, cyanate esters,vinyl ethers, vinyl esters, styrenic compounds and allyl functionalcompounds; 0 to about 90 wt % of a filler; 0 wt % to about 5 wt % of atleast one curing initiator, based on total weight of the composition;0.1 wt % to about 4 wt %, of at least one coupling agent, based on totalweight of the composition.

Curing Initiators. In certain embodiments, the present inventionprovides compositions, such as adhesive compositions, including at leastone hyperbranched monomer or polymer of the invention and at least onecuring initiator. The curing initiator is typically present in adhesivecompositions of the invention at an amount from 0.1 wt % to about 5 wt%, based on total weight of the composition, and is typically afree-radical initiator. In some embodiments, the curing initiator ispresent at least about 0.5 wt %, often at least about 1 wt %, frequentlyat least about 2 wt %, at in some embodiments at least about 3 wt %,based on total weight of the composition.

Free-radical initiators contemplated for use in the practice of thepresent invention typically decompose (i.e., have a half life in therange of about 10 hours) at temperatures in the range of about 70° C. upto 180° C. Exemplary free radical initiators contemplated for use in thepractice of the present invention include peroxides (e.g. dicumylperoxide, dibenzoyl peroxide, 2-butanone peroxide, tert-butylperbenzoate, di-tert-butyl peroxide,2,5-bis(tert-butylperoxy)-2,5-dimethylhexane, bis(tert-butylperoxyisopropyl)benzene, and tert-butyl hydroperoxide), azo compounds(e.g., 2,2′-azobis(2-methyl-propanenitrile),2,2′-azobis(2-methylbutanenitrile), and1,1′-azobis(cyclohexanecarbonitrile)). Other free-radical initiatorsthat will be well-known in the art may also be suitable for use in thecompositions of the present invention.

Photoinitiators. Free radical initiators also include photoinitiators.For invention compositions that contain a photoinitiator, the curingprocess can be initiated, for example, by UV radiation. In oneembodiment, the photoinitiator is present at a concentration of 0.1 wt %to 5 wt %, based on the total weight of the organic compounds in thecomposition (excluding any filler). In one embodiment, thephotoinitiator comprises 0.5 wt % to 3.0 wt %, based on the total weightof the organic compounds in the composition. In other embodiments, thephotoinitiator is present at least about 0.5 wt %, often at least about1 wt %, frequently at least about 2 wt %, and in some embodiments atleast about 3 wt %, based on the total weight of the organic compoundsin the composition. Photoinitiators include benzoin derivatives,benzilketals, α,α-dialkoxyacetophenones, α-hydroxyalkylphenones,α-aminoalkylphenones, acylphosphine oxides, titanocene compounds,combinations of benzophenones and amines or Michler's ketone, and thelike.

In some embodiments, both photoinitiation and thermal initiation may bedesirable. For example, curing of a photoinitiator-containing adhesivecan be started by UV irradiation, and in a later processing step, curingcan be completed by the application of heat to accomplish a free-radicalcure. Both UV and thermal initiators may therefore be added to theadhesive compositions of the invention.

In other embodiments the initiator is an anionic catalyst. Examples ofanionic initiators include Lewis bases such as tertiary amines andimidazoles. Specific examples include benzyldimethlamine, triethylamine,tripropylamine, pyridine, dimethylaminopyridine, dimethylethanolamine,diethylethanolamine, tributylamine, 2-methylimidazole,2-undecylimidazole, 1-benzyl-2-methylimidazole,1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole,1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole,1-cyanoethyl-2-isopropylimidazole,1-cyanoethyl-2-methylimidazole-trimellitate,1-cyanoethyl-2-phenylimidazole-trimellitate,1-cyanoethyl-2-ethyl-4-methylimidazole-trimellitate,1-cyanoethyl-2-undecylimidazole-trimellitate,2,4-diamino-6-(2′methylimidazolyl-(1′))ethyl-s-triazine,2,4-diamino-6-(2′-ethyl-4′-methyl-imidazolyl-(1′))ethyl-s-triazine,2,4-diamino-6-(2′-undecylimidazolyl-(1′))ethyl-s-triazine,2-phenyl-4-methyl-5-hydroxymethylimidazole,2-phenyl-4,5-dihydroxymethylimidazole,1-cyanoethyl-2-phenyl-4,5-di(cyanoethoxymethyl)imidazole,2-methylimidazole-isocyanuric acid addition compound,2-phenylimidazole-isocyanuric acid addition compound,2,4-diamino-6[2′-methylimidazolyl-(1)′]ethyl-s-triazine isocyanurateadduct, 4,4-methylene-bis-(2-ethyl-5-methylimidazole), and the like.

In other embodiments the initiator is a cationic catalyst. Specificexamples include onium compounds. Specific examples includebis[4-(diphenylsulphonio)-phenyl]sulphide bis-hexafluorophosphate,bis[4-(di(2-hydroxyethyl)phenyl)sulphonio-phenyl]sulphidebis-hexafluorophosphate,bis[4-(di(4-(2-hydroxyethyl)phenyl)sulphonio)phenyl]sulphidebis-hexafluoroantimonate,(η⁵-2,4-(cyclopentadienyl)[(1,2,3,4,5,6-η)-(methylethyl)-benzene]-iron(II)hexafluorophosphate, triarylsulphonium hexafluorophosphate,(tolylcumyl)iodonium tetrakis (pentafluorophenyl) borate, diaryliodonium hexafluoroantimonate, and the like. In certain embodiments, theinvention provides adhesive compositions including 0.5 wt % to about 98wt % of at least one hyperbranched compound described herein, based ontotal weight of the composition; optionally, 10 wt % o about 90 wt % ofat least one co-monomer selected from acrylates, methacrylates,maleimides, vinyl ethers, vinyl esters, styrenic compounds, allylfunctional compounds, and olefins, based on total weight of thecomposition; 0 to about 90 wt % of a conductive filler; 0.1 wt % toabout 5 wt % of at least one curing initiator, based on total weight ofthe composition; and 0.1 wt % to about 4 wt %, of at least one couplingagent, based on total weight of the composition.

Additional Co-Curing Compounds. In certain aspects, the adhesivecompositions of the invention include at least one additional compoundthat can co-cure with the hyperbranched monomers and/or polymers of theinvention. The additional compound is typically present in the adhesivecompositions from about 10 wt % to about 90 wt % based on total weightof the composition. In such aspects, the composition will typicallycontain an amount of the co-curing compound equal to at least about 20wt %, often at least about 30 wt %, frequently at least about 40 wt %,and in some embodiments at least about 50 wt % based on the total weightof the composition. Such compounds include, for example, epoxies (e.g.epoxies based on glydicyl ethers of alcohols, phenols, bisphenols,oligomeric phenolics, phenolic novolacs, cresolic novolacs, acrylates,methacrylates, maleimides, poly-phenol compounds (e.g.poly(4-hydroxystyrene)), anhydrides, dianhydrides, polyanhydrides suchas styrene-maleic anhydride co-polymers, imides, carboxylic acids,dithiols, polythiols, phenol functional mono-maleimides, bismaleimides,polymaleimides, mono-itaconates, mono-maleates, mono-fumarates, acrylicacid, methacrylic acid, cyanate esters, vinyl ethers, vinyl esters, orphenol functional esters, ureas, amides, polyolefins (e.g. amine,carboxylic acid, hydroxy, and epoxy functional) siloxanes (e.g. epoxy,phenolic, carboxylic acid, or thiol functional), cyanoacrylates, allylfunctional compounds and styrenic, as well as combinations thereof.

Coupling Agents. In certain aspects, the adhesive compositions of theinvention include at least one additional coupling agent. Exemplarycoupling agents contemplated for use in the practice of the presentinvention include silicate esters, metal acrylate salts (e.g., aluminummethacrylate), titanates (e.g., titanium methacryloxyethylacetoacetatetriisopropoxide), zirconates, or compounds that contain acopolymerizable group and a chelating ligand (e.g., phosphine,mercaptan, acetoacetate, and the like). In some embodiments, thecoupling agent contains both a co-polymerizable function (e.g., vinyl,acrylate, methacrylate, epoxy, thiol, anhydride, isocyanate, and phenolmoieties) and a silicate ester function. The silicate ester portion ofthe coupling agent is capable of condensing with metal hydroxidespresent on the mineral surface of substrate, while the co-polymerizablefunction is capable of co-polymerizing with the other reactivecomponents of invention adhesive compositions, such as die-attachpastes. In certain embodiments coupling agents contemplated for use inthe practice of the invention are oligomeric silicate coupling agentssuch as poly(methoxyvinylsiloxane).

Adhesive Paste Compositions Containing Hyperbranched Compound

In certain embodiments, the present invention provides adhesivecompositions that are of various consistencies including, liquids, gels,pastes and solids. In one embodiment, the adhesive composition is apaste suitable for attaching an electronics die to a substrate (i.e.,die-attach pastes). Die attach pastes of the invention are optimized forlong-term reliability, rapid inline curing, long pot-life, viscosity andthixotropic control for fast automated dispensing and manufacturing.

In one embodiment, the present invention provides an adhesivecomposition that include 0.5 wt % to about 98 wt % based on total weightof the composition, of a hyperbranched monomer and/or polymer of theinvention; 0 to about 90 wt % of a filler, based on total weight of thecomposition; 0.1 wt % to about 5 wt % of at least one curing initiator,based on total weight of the composition; and 0.1 wt % to about 4 wt %,of at least one coupling agent, based on total weight of thecomposition.

B-Stageable Adhesives

In certain embodiments, the adhesive compositions and die attach pastesof the invention are b-stageable. As used herein, “B-stageable” refersto the properties of an adhesive having a first solid phase followed bya tacky rubbery stage at elevated temperature, followed by yet anothersolid phase at an even higher temperature. The transition from therubbery stage to the second solid phase is thermosetting. However, priorto that, the thermosetting material behaves similarly to a thermoplasticmaterial. Thus, such adhesives allow for low lamination temperatureswhile providing high thermal stability.

The B-stageable adhesive can be dispensed onto a die or a substrate by avariety of methods well known to those skilled in the art. In someembodiments, the adhesive is cast from solution using techniques such asspin coating, spray coating, stencil printing, screen printing, and thelike. This dual stage cure is especially attractive for applicationswere it is desirable to apply an adhesive in liquid form, cure thematerial to a non-tacky thermoplastic state, and then cure this B-stagedadhesive in a final heating step to bond two or more parts together.Thus, this dual stage cure method of the invention is particularlyadvantageous for silicon wafer back coatings. The original adhesivemixture can be spin coated onto the back of a silicon wafer. The coatingcan then be B-staged with heat or light. The coated wafers can then bediced to yield individual microelectronic components, which may bethermally attached directly to a substrate, and/or stacked together. Thethermal “tacking step” re-liquifies the adhesive coating and provides athermoplastic bond between the parts. The final bonding step involves athermal (or in some cases light-based) cure to cross-link the B-stagedadhesive composition. This method of assembly is highly desirablebecause it is easier to manufacture (especially for stacked die) than atraditional liquid adhesive assembly, and is much less expensive andwasteful compared to film-based adhesive technology.

In certain embodiments, a solvent may be employed in the practice of theinvention. For example, when the B-stageable adhesive is spin-coatedonto a circular wafer, it is desirable to have an even coatingthroughout the entire wafer, i.e., the solvent or solvent system shouldhave the ability to deliver the same amount of adhesive to each point onthe wafer. Thus, the adhesive will be evenly coated throughout, i.e.,there will be the same amount of material at the center of the wafer asat the edges. Ideally, the adhesive is “Newtonian”, with a thixotropicslope of 1.0. In certain embodiments, the solvent or solvent systemsused to dispense the B-stageable adhesive have slopes ranging from 1.0to about 1.2.

In some instances, the B-stageable adhesive is dispensed onto thebackside of a die that has been coated with a polyimide. Thus, thesolvent or solvent system used to dispense the B-stageable adhesiveshould not have any deleterious effects on the polyimide coating. Toachieve this goal, in certain embodiments, the solvent system willinclude a polar solvent in combination with a nonpolar solvent.Typically, the polar solvent is suitable for use with the hyperbranchedcompound described herein in B-stageable adhesives, and the nonpolarsolvent is a non-solvent for the hyperbranched compound. In addition,the polar solvent typically has a lower boiling point than the non-polarsolvent. Without wishing to be to be limited to a particular theory, itis believed that when the adhesive is dispensed and then B-staged, thelower boiling polar solvent escapes first, leaving behind only thenonpolar non-solvent, essentially precipitating the oligomer uniformlyand leaving the polyimide film undamaged.

In some embodiments, the solvent or solvent system has a boiling pointranging from about 150° C. up to about 300° C. In some embodiments, thesolvent system is a combination of dimethyl phthalate (DMP), NOPAR 13,and terpineol. In other embodiments, the solvent system is a 1:1 (byvolume) ratio of terpineol and NOPAR 13.

In general, adhesive compositions such as die-attach pastes andB-stageable adhesive compositions of the invention, will cure within atemperature range of 80-220° C., and curing will be effected within alength of time of less than 1 minute up to about 60 minutes. TheB-stageable adhesive composition may be pre-applied onto either asemiconductor die or onto a substrate. As will be understood by thoseskilled in the art, the time and temperature curing profile for eachadhesive composition will vary, and different compositions can bedesigned to provide the curing profile that will be suited to aparticular industrial manufacturing process.

Additional Compounds. In certain embodiments, the compositions of theinvention, such as adhesives (including die-attach paste adhesives), maycontain modifiers that lend additional flexibility and toughness to theresultant cured adhesive. Such modifiers may be any thermoset orthermoplastic material having a T_(g) of 50° C. or less, and typicallywill be a polymeric material characterized by free rotation about thechemical bonds, the presence of ether groups, and the absence of ringstructures. Suitable such modifiers include polyacrylates,poly(butadiene), polyTHF (polymerized tetrahydrofuran, also known aspoly(1,4-butanediol)), CTBN (carboxy-terminated butadiene-acrylonitrile)rubber, and polypropylene glycol. When present, toughening compounds maybe present in an amount up to about 15 percent by weight ofhyperbranched monomer and/or polymer of the invention and any othermonomer in the adhesive.

Inhibitors for free-radical cure may also be added to the adhesivecompositions and die-attach pastes described herein to extend the usefulshelf life. Examples of free-radical inhibitors include hindered phenolssuch as 2,6-di-tert-butyl-4-methylphenol;2,6-di-tert-butyl-4-methoxyphenol; tert-butyl hydroquinone;tetrakis(methylene(3,5-di-tert-butyl-4-hydroxyhydrocinnamate))benzene;2,2′-methylenebis(6-tert-butyl-p-cresol); and1,3,5-trimethyl-2,4,6-tris(3′,5′-di-tert-butyl-4-hydroxybenzyl)benzene.Other useful hydrogen-donating antioxidants such as derivatives ofp-phenylenediamine and diphenylamine. It is also well know in the artthat hydrogen-donating antioxidants may be synergistically combined withquinones and metal deactivators to make a very efficient inhibitorpackage. Examples of suitable quinones include benzoquinone, 2-tertbutyl-1,4-benzoquinone; 2-phenyl-1,4-benzoquinone; naphthoquinone, and2,5-dichloro-1,4-benzoquinone. Examples of metal deactivators includeN,N′-bis(3,5-di-tert-butyl-4-hydroxyhydrocinnamoyl)hydrazine; oxalylbis(benzylidenehydrazide); andN-phenyl-N′-(4-toluenesulfonyl)-p-phenylenediamine. Nitroxyl radicalcompounds such as TEMPO (2,2,6,6-tetramethyl-1-piperidnyloxy, freeradical) are also effective as inhibitors at low concentrations. Thetotal amount of antioxidant plus synergists typically falls in the rangeof 100 to 2000 ppm relative to the weight of total base resin. Otheradditives, such as adhesion promoters, in types and amounts known in theart, may also be added.

The adhesive compositions, such as die-attach paste adhesives, describedherein will generally perform within the commercially acceptable rangesfor die attach adhesives. Commercially acceptable values for die shearfor the adhesives on a 80×80 mil² silicon die are in the range ofgreater than or equal to 1 kg at room temperature, and greater than orequal to 0.5 kg at 260° C. Acceptable values for warpage for a 500×500mil² die are in the range of less than or equal to 70 Nm at roomtemperature.

Fillers. In some embodiments, fillers are contemplated for use in thepractice of the present invention, which can be electrically conductiveand/or thermally conductive, and/or fillers which act primarily tomodify the rheology of the resulting composition. Examples of suitableelectrically conductive fillers that can be employed in the practice ofthe present invention include silver, nickel, copper, aluminum,palladium, gold, graphite, metal-coated graphite (e.g., nickel-coatedgraphite, copper-coated graphite, and the like), and the like. Examplesof suitable thermally conductive fillers that can be employed in thepractice of the present invention include graphite, aluminum nitride,silicon carbide, boron nitride, diamond dust, zinc oxide, alumina, andthe like. Compounds which act primarily to modify rheology includepolysiloxanes (such as polydimethyl siloxanes), silica, fumed silica,fumed alumina, fumed titanium dioxide, calcium carbonate and the like.

Underfill Compositions

During its normal service life, an electronic assembly is subjected torepeated cycles of widely varying temperature. Due to the differences inthe coefficient of thermal expansion between the electronic component,the solder, and the substrate, thermal cycling can stress the componentsof the assembly and cause it to fail. To prevent the failure, the gapbetween the component and the substrate is filled with an underfillmaterial to reinforce the solder material and to absorb some of thestress of the thermal cycling.

In practice, the underfill material is typically dispensed into the gapbetween and electronic component (such as a flip-chip) and the substrateby injecting the underfill along two or more sides of the component,with the underfill material flowing, usually by capillary action, tofill the gap. Alternatively, underfilling can be accomplished bybackfilling the gap between the electronic component and the substratethrough a hole in the substrate beneath the chip. In either method, theunderfill material must be sufficiently fluid to permit filling verysmall gaps.

The requirements and preferences for underfills are well known in theart. Specifically, monomers for use in underfills should have high Tgand low α₁ CTE, important properties. A high Tg, preferably in the rangeof at least about 100-135° C., and a low modulus or α₁, preferably lowerthan about 60-65 ppm/° C., are optimal for underfill compositions.

The hyperbranched compounds of the invention are particularly suited asmonomers or co-monomers in underfill composition. Thus, the presentinvention provides underfill compositions including at least onecompound hyperbranched monomer and/or polymer of the invention.Optionally, the underfill will also contain a fluxing agent and/or afiller.

Two prominent uses for underfill technology are in packages known in theindustry as flip-chip, in which a chip is attached to a lead frame, andball grid array, in which a package of one or more chips is attached toa printed wire board.

The underfill encapsulation may take place after the reflow of themetallic or polymeric interconnect, or it may take place simultaneouslywith the reflow. If underfill encapsulation takes place after reflow ofthe interconnect, a measured amount of underfill encapsulant materialwill be dispensed along one or more peripheral sides of the electronicassembly and capillary action within the component-to-substrate gapdraws the material inward. The substrate may be preheated if needed toachieve the desired level of encapsulant viscosity for the optimumcapillary action. After the gap is filled, additional underfillencapsulant may be dispensed along the complete assembly periphery tohelp reduce stress concentrations and prolong the fatigue life of theassembled structure. The underfill encapsulant is subsequently cured toreach its optimized final properties.

If underfill encapsulation is to take place simultaneously with reflowof the solder or polymeric interconnects, the underfill encapsulant,which can include a fluxing agent if solder is the interconnectmaterial, first is applied to either the substrate or the component;then terminals on the component and substrate are aligned and contactedand the assembly heated to reflow the metallic or polymeric interconnectmaterial. During this heating process, curing of the underfillencapsulant occurs simultaneously with reflow of the metallic orpolymeric interconnect material.

A wide variety of acids are contemplated for use as the acidic fluxingagent. Typically, the acidic fluxing agent is a carboxylic acid such as,for example, 3-cyclohexene-1-carboxylic acid, 2-hexeneoic acid,3-hexeneoic acid, 4-hexeneoic acid, acrylic acid, methacrylic acid,crotonic acid, vinyl acetic acid, tiglic acid, 3,3-dimethylacrylic acid,trans-2-pentenoic acid, 4-pentenoic acid, trans-2-methyl-2-pentenoicacid, 2,2-dimethyl-4-pentenoic acid, trans-2-hexenoic acid,trans-3-hexenoic acid, 2-ethyl-2-hexenoic acid, 6-heptenoic acid,2-octenoic acid, (+/−)-citronellic acid, (R)-(+)-citronellic acid,(S)-(−)-citronellic acid, undecylenic acid, myristolic acid, palmitoleicacid, oleic acid, elaidic acid, cis-11-eicosenoic acid, erucic acid,nervonic acid, cis-3-chloroacrylic acid, trans-3-chloroacrylic acid,2-bromoacrylic acid, 2-(trifluoromethyl)acrylic acid,2-(bromomethyl)acrylic acid, 2-cyclopentene-1-acetic acid,(1R-trans)-2-(bromomethyl)-2-methyl-3-methylenecyclopentaneacetic acid,2-acetamidoacrylic acid, 5-norbornene-2-carboxylic acid,3-(phenylthio)acrylic acid, trans-styrylacetic acid, trans-cinnamicacid, alpha-methylcinnamic acid, alpha-phenylcinnamic acid,2-(trifluoromethyl)cinnamic acid, 2-chlorocinnamic acid,2-methoxycinnamic acid, cis-2-methoxycinnamic acid, 3-methoxycinnamicacid, 4-methylcinnamic acid, 4-methoxycinnamic acid,2,5-dimethoxycinnamic acid, 3,4-(methylenedioxy)cinnamic acid,2,4,5-trimethoxycinnamic acid, 3-methylindene-2-carboxylic acid, andtrans-3-(4-methylbenzoyl)acrylic acid, oxalic acid, malonic acid,methylmalonic acid, ethylmalonic acid, butylmalonic acid,dimethylmalonic acid, diethylmalonic acid, succinic acid, methylsuccinicacid, 2,2-dimethylsuccinic acid, 2-ethyl-2-methylsuccinic acid,2,3-dimethylsuccinic acid, meso-2,3-dimethylsuccinic acid, glutaricacid, (+/−)-2-methylglutaric acid, 3-methylglutaric acid,2,2-dimethylglutaric acid, 2,4-dimethylglutaric acid,3,3-dimethylglutaric acid, adipic acid, 3-methyladipic acid,(R)-(+)-3-methyladipic acid, 2,2,5,5-tetramethylhexanedioic acid,pimelic acid, suberic acid, azelaic acid, 1,10-decanedicarboxylic acid,sebacic acid, 1,11-undecanedicarboxylic acid, undecanedioic acid,1,12-dodecanedicarboxylic acid, hexadecanedioic acid, docosanedioicacid, tetracosanedioic acid, tricarballylic acid,beta-methyltricarballylic acid, 1,2,3,4-butanetetracarboxylic acid,itaconic acid, maleic acid, fumaric acid, citraconic acid, mesaconicacid, trans-glutatonic acid, trans-beta-hydromuconic acid,trans-traumatic acid, trans,trans-muconic acid, cis-aconitic acid, transaconitic acid, (+/−)-chlorosuccinic acid, (+/−)-bromosuccinic acid,meso-2,3-dibromosuccinic acid, hexa fluoroglutaric acid, perfluoroadipicacid hydrate, dibromo-maleic acid, DL-malic acid, D-malic acid, L-malicacid, (R)-(−)-citramalic acid, (S)-(+)-citramalic acid,(+/−)-2-isopropylmalic acid, 3-hydroxy-3-methylglutaric acid,ketomalonic acid monohydrate, DL-tartaric acid, L-tartaric acid,D-tartaric acid, mucic acid, citric acid, citric acid monohydrate,dihydroflumaric acid hydrate, tetrahydrofuran-2,3,4,5-tetracarboxylicacid, mercaptosuccinic acid, meso-2,3-dimercaptosuccinic acid,thiodiglycolic acid, 3,3′-thiodipropionic acid, 3,3′-dithiodipropionicacid, 3-carboxypropyl disulfide, (+/−)-2-(carboxymethylthio)succinicacid, 2,2′,2″,2′″-[1,2-ethanediylidenetetrakis(thio)]-tetrakisaceticacid, nitromethanetrispropionic acid, oxalacetic acid, 2-ketoglutaricacid, 2-oxoadipic acid hydrate, 1,3-acetonedicarboxylic acid,3-oxoadipic acid, 4-ketopimelic acid, 5-oxoazelaic acid, chelidonicacid, 1,1-cyclopropanedicarboxylic acid, 1,1-cyclobutanedicarboxylicacid, (+/−)-trans-1,2-cyclobutanedicarboxylic acid,trans-DL-1,2-cyclopentanedicarboxylic acid, 3,3-tetramethyleneglutaricacid, (1R.3S)-(+)-camphoric acid, (1S.3R)-(−)-camphoric acid,(+/−)-cyclohexylsuccinic acid, 1,1-cyclohexanediacetic acid,(+/−)-trans-1,2-cyclohexanedicarboxylic acid,(+/−)-1,3-cyclohexanedicarboxylic acid,trans-1,2-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylicacid, 1,3-adamantanedicarboxylic acid,3-methylenecyclopropane-trans-1,2-dicarboxylic acid,cis-5-norbomene-endo-2,3-dicarboxylic acid,1,3,5-cyclohexanetricarboxylic acid, 1,3,5-cyclohexanetricarboxylicacid, kemp's triacid,(1alpha.3alpha.5beta)-1,3,5-trimethyl-1,3,5-cylohexanetricarboxylicacid, 1,2,3,4-cyclobutane-tetracarboxylic acid, and1,2,3,4,5,6-cyclo-hexanehexacarboxylic acid monohydrate, phenylmalonicacid, benzylmalonic acid, phenylsuccinic acid, 3-phenylglutaric acid,1,2-phenylenediacetic acid, homophthalic acid, 1,3-phenylenediaceticacid, 4-carboxyphenoxyacetic acid, 1,4-phenylenediacetic acid,2,5-dihydroxy-1,4-benzenediacetic acid, 1,4-phenylenediacrylic acid,phthalic acid, isophthalic acid, 1,2,3-benzenetricarboxylic acidhydrate, terephthalic acid, 1,2,4-benzenetricarboxylic acid,1,2,4,5-benzenetetracarboxylic acid, mellitic acid,3-(carboxymethylaminomethyl)-4-hydroxybenzoic acid, 4-methylphthalicacid, 2-bromoterephthalic acid, 4-bromoisophthalic acid,4-hydroxyisophthalic acid, 4-nitrophthalic acid, nitrophthalic acid,1,4-phenylenedipropionic acid, 5-tert-butylisophthalic acid,5-hydroxyisophthalic acid, 5-nitroisophthalic acid,5-(4-carboxy-2-nitrophenoxy)-isophthalic acid, diphenic acid,4,4′-biphenyldicarboxylic acid, 5,5′dithiobis(2-nitrobenzoic acid),4-[4-(2-carboxybenozoyl)phenyl]-butyric acid, pamoic acid,1,4-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid,2,6-naphthalenedicarboxylic acid, 1,4,5,8-naphthalene-tetracarboxylicacid hydrate, 2,7-di-tert-butyl-9,9-dimethyl-4,5-xanthenedicarboxylicacid, and the like.

A particularly useful carboxylic acid for the preparation of the latentfluxing agents of the present invention is DIACID 1550®, a monocyclicC₂₁ dicarboxylic acid product derived from tall oil fatty acids,commercially available from Westvaco Corporation.

Mold Compounds and Compositions

In the electronics industry, a semiconductor chip or die mounted to a“package” substrate may be overmolded with a mold compound to provide alevel of protection from environmental effects such as moisture andcontaminants.

In terms of reliability performance, various properties of moldcompositions materials are generally considered important. Theproperties desirable for mold compositions are known in the art. See,for example, U.S. Pat. Nos. 7,294,915, 6,512,031, and 6,429,238. Theseinclude low CTE, low modulus, adhesion, and high fracture toughness ofthe cured resin. A high Tg, preferably in the range of at least about100-135(C, and a low modulus or α₁, preferably lower than about 60-65ppm/(C, are optimal for mold compositions. See, for example, U.S. Pat.Nos. 6,512,031 and 5,834,848. A typical overmolding process places asolid or semi-solid molding compound over the chip using a mold press.The package is then transferred through a heated mold that causes themolding compound to flow and encapsulate the chip.

Mold compositions are highly filled compositions. They are typicallyfilled with silica. This high filler loading is critical to theirperformance in terms of CTE (coefficient of thermal expansion), flameretardance, and thermal conductivity.

The compounds of the present invention were found to have propertiesdesirable of mold compounds. Thus, the present invention provides moldcompositions containing at least one hyperbranched monomer and/orpolymer of the invention.

Assemblies

The present invention also provides assemblies of components adheredtogether by the above-described adhesive compositions (e.g., B-stageableadhesives and die-attach pastes) of the invention. Thus, for example,assemblies comprising a first article adhered to a second article by acured aliquot of an adhesive composition containing at least onehyperbranched compound described herein are provided. Articlescontemplated for assembly employing invention compositions includeelectronic components such as dies, memory devices (e.g. as flash memorydevices), ASIC devices, microprocessors, and other microelectroniccomponents. Assemblies also include microelectronic devices, such ascopper lead frames, Alloy 42 lead frames, silicon dice, gallium arsenidedice, and germanium dice, that are adhered to a substrate by a curedaliquot of the above-described adhesive compositions

Additional embodiments of the invention include adhesively bondedstructures containing at least one hyperbranched compound describedherein. Non-limiting examples of the adhesively bonded structuresinclude electronic components bonded to a substrate, and circuitcomponents bonded to printed wire boards. In other embodiments of theinvention, articles of manufactures can be comprised substantially of acured amount of the composition described herein, such as an industrial,marine, automotive, airline, aerospace, sporting goods, medical ordental article. Such articles of manufacture can also include fillers,extenders, pigments and/or reinforcing materials along with thecompositions disclosed herein.

Conditions suitable to cure invention die attach paste adhesives includesubjecting the above-described assembly to a temperature of less thanabout 200° C. for about 0.5 up to 2 minutes. This rapid, short durationheating can be accomplished in a variety of ways, e.g., with an in-lineheated rail, a belt furnace, or the like. Optionally, the material canbe oven cured at 150-220° C.

Methods of Using Hyperbranched Compounds and Adhesive Compositions

According to the present invention, methods for adhesively attaching afirst article to a second article are provided. Such methods can beperformed, for example, by a) applying an adhesive composition of theinvention to the first article, the second article or both the first andsecond articles; b) contacting the first article and the second article,where the first article and the second article are separated only by theadhesive composition applied in step a); and c) curing the adhesivecomposition applied in step a), thereby adhesively attaching the firstarticle to the second article.

In one aspect of this method, the first and second articles are asemiconductor die and a substrate, respectively. Typically, according tothis aspect the adhesive is a die attach paste. The method can includethe steps of applying the adhesive composition (e.g. die attach paste)to the substrate, the semiconductor die, or both the substrate and thesemiconductor die; b) melting the adhesive composition applied in stepa); c) contacting the semiconductor device and the substrate, where thedie and substrate are separated only by the adhesive composition appliedin step a); and d) curing the adhesive composition applied in step a),thereby adhesively attaching the semiconductor device to the substrate.Applying the adhesive composition can include spin-coating, spraycoating, stencil printing, screen printing and other methods well knownin the art.

It will be understood those of skill in the art that using the compoundsand methods of the present invention, it is possible to prepareadhesives having a wide range of cross-link density by the judiciouschoice and amount of a hyperbranched monomer and/or polymer of theinvention. The greater proportion of polyfunctional compounds reacted,the greater the cross-link density. If thermoplastic properties aredesired, the adhesive compositions can be prepared from (or at leastcontain a higher percentage of) mono-functional compounds to limit thecross-link density. A minor amount of poly-functional compounds can beadded to provide some cross-linking and strength to the composition,provided the amount of poly-functional compounds is limited to an amountthat does not diminish the desired thermoplastic properties. Withinthese parameters, the strength and elasticity of individual adhesivescan be tailored to a particular end-use application.

In still further embodiments, the invention provides B-stageable typemethods for adhesively attaching a semiconductor die to a substrate.Such methods can be performed, for example, by applying an inventionadhesive composition to the substrate, the semiconductor device or boththe substrate and the semiconductor device; melting the applied adhesivecomposition applied; (c) contacting the semiconductor device and thesubstrate, such that the die and substrate are separated only by theapplied adhesive composition; and curing the applied adhesivecomposition, thereby attaching the semiconductor device to thesubstrate.

Properties of Adhesives Containing Hyperbranched Compounds

Advantageously, the hyperbranched compounds of the invention can impartmany properties that are desirable in an adhesive. Historically, thelarge majority of integrated circuits have been mounted on printedcircuit boards using lead-based soldering. However, the demand forlead-free materials is increasing year by year, and electricallyconductive adhesives are seen as an environmentally-friendlyalternative.

Adhesiveness. To fully replace lead-based solders, adhesives in themicroelectronic industry, adhesives must address the need for signal andpower distribution, heat dissipation (i.e., cooling) while at the sametime having and maintaining high adhesiveness. Conductive adhesives, forexample, typically have conductive fillers dispersed in a polymermatrix. The polymer matrix, when cured, provides the mechanicaladhesion, but can interfere with conductivity and increase electricalresistance.

In yet another embodiment, the present invention provides methods forincreasing the adhesiveness (i.e. adhesion or adhesive strength) of anadhesive including the steps of mixing a molar excess of at least onebismaleimide with at least one di-cinnamyl compound, and heating themixture, thereby increasing the adhesive strength of the curedbismaleimide. In certain embodiments, the adhesive strength will beincreased by 10-75%. Typically, this method increases the adhesivestrength by at least about 10%, frequently by at least about 25%, oftenby at least about 50% and can increase the adhesive strength by at leastabout 65% or more.

Thus the present invention provides methods for increasing theadhesiveness of an adhesive composition by replacing all or a portion ofa monomer (such as an acrylate or maleimide monomer) in the composition,with a hyperbranched compound of the invention.

The invention will now be further described with reference to thefollowing non-limiting examples.

EXAMPLES Example 1 Synthesis of Compound 1:(2-(2-(bis(2-hydroxyethyl)amino)-2-oxoethyl)-3,5,7,9-tetramethyldec-3-enoicacid)

A 500 ml, two-neck flask was charged with 52.6 g (500 mmol)diethanolamine and 50 ml toluene. A temperature probe was placed intothis solution through one of the necks of the flask and the flask wasimmersed into a water bath. A solution of 133.4 g (500 mmol)dodecenylsuccinic anhydride dissolved in 125 ml toluene was dripped intothe magnetically stirred solution diethanolamine solution over athirty-five minute period. Ice was added to the water bath as requiredto prevent temperature of the reaction mixture from getting above 30° C.The mixture was then stirred for another two hours at room temperature.The complete disappearance of the anhydride functional group wasconfirmed by infrared spectroscopy. The FTIR trace on this compoundshowed significant absorptions at 2960, 1733, 1626, 1569, 1456, 1380,1161, 1065, and 728 wavenumbers. The solution was concentrated down to50% solids with toluene and then set aside for later use.

Example 2 Synthesis of Compound 2:(2-(2-(bis(2-hydroxyethyl)amino)-2-oxoethyl)dec-3-enoic acid)

A 500 ml, two-neck flask was charged with 52.6 g (500 mmol)diethanolamine and 50 ml toluene. A temperature probe was placed intothis solution through one of the necks of the flask and the flask wasimmersed into a water bath. A solution of 105.2 g (500 mmol)dodecenylsuccinic anhydride dissolved in 200 ml toluene was dripped intothe magnetically stirred solution diethanolamine solution over a40-minute period. Ice was added to the water bath as required to preventtemperature of the reaction mixture from getting above 25° C. Themixture was then stirred for another 2.5 hours at room temperature. Thecomplete disappearance of the anhydride functional group was confirmedby infrared spectroscopy. The FTIR trace on this compound hadsignificant absorptions at 2957, 2924, 2858, 1733, 1616, 1560, 1415,1160, 1069, 969, and 728 wavenumbers. The solution was concentrated downto 50% solids in toluene and was then set aside for later use.

Example 3 Synthesis of Compound 3:(2-(2-(diallylamino)-2-oxoethyl)-3,5,7,9-tetramethyldec-3-enoic acid)

A 500 ml, two-neck flask was charged with 133.4 g (500 mmol)dodecenylsuccinic anhydride 100 ml toluene. The flask was equipped witha thermometer and immersed in a water bath. Diallylamine (48.6 g, 500mmol) was then dripped into the magnetically stirred anhydride plustoluene solution over a twenty-five minute period. Ice was added to thewater bath as required to prevent temperature of the reaction mixturefrom getting above 35° C. The mixture was then stirred for another 1.5hours at room temperature. The toluene was then removed via rotaryevaporator and air sparge to yield 181.4 g (99.8% of theory) of a red,viscous, oily liquid. The FTIR trace on this compound showed significantabsorptions at 2959, 1727, 1643, 1414, 1185, 991, and 921 wavenumbers.

Example 4 Synthesis of Compound 4:(2-(2-(diallylamino)-2-oxoethyl)dec-3-enoic acid)

A 500 ml, two-neck flask was charged with 105.2 g (500 mmol)dodecenylsuccinic anhydride 100 ml toluene. The flask was equipped witha thermometer and immersed in a water bath. Diallylamine (48.6 g, 500mmol) was then dripped into the magnetically stirred anhydride plustoluene solution over a 15-minute period. Ice was added to the waterbath as required to prevent temperature of the reaction mixture fromgetting above 35° C. The mixture was then stirred for another 45 minutesat room temperature. The toluene was then removed via rotary evaporatorand air sparge to yield 153.4 g (99.8% of theory) of a red, oily liquid.An FTIR trace on this compound was found to have significant absorptionsat 2924, 1726, 1605, 1440, 1221, 1174, 972, and 922 wavenumbers.

Example 5 Synthesis of Compound 6: (Hyperbranched Amide-EsterPolymethacrylate)

A 500 ml, two-neck flask was charged with 137.4 g (200 mmol) of Compound1 as a 50% solution in toluene, 17.8 g (50 mmol) Simulsol PTKE (SeppicUK, Ltd. Hounslow, England), and a magnetic stir bar. A temperaturecontroller, Dean-Stark trap, condenser, and bubbler were attached. Theflask was purged with argon and the mixture was then brought up toreflux at a pot temperature of 150° C. (it was necessary to removeexcess toluene in order to attain this temperature). The generation ofwater through the non-catalyzed esterification reaction becamesignificant once the reaction temperature rose above about 120° C. Thiscondensation reaction was continued for three hours and 4.5 ml of waterwas collected. The pot temperature was then reduced to 60° C. and 50 mltoluene, 61.6 g (400 mmol) methacrylic anhydride and 0.2 g DMAP catalystwas added. This new mixture was stirred at 60° C. for 48 hours. Thesolution was cooled to room temperature, diluted with another 200 mltoluene and then extracted with 4×25 ml brine washes. The solution wasthen stirred with 45 g NaHCO₃ until all CO₂ evolution had ceased. Themix was dried with 15 g MgSO₄ and then passed over 25 g silica gel. Thetoluene was removed via rotary evaporation followed by air sparge. Theproduct was a very viscous (19,219 centipoise at 60° C.@5 rpm) orangeliquid that weighed 96.36 g (87.4% of theory). An FTIR trace on thiscompound revealed significant absorptions at 2957, 1722, 1640, 1452,1295, 1157, 939, and 921 wavenumbers. Thermogravimetric analysis (TGA)was run on this compound (ramp rate at 10° C./minute, air purge) theresidual weight was 99.3% at 200° C. and 96.8% at 300° C. Thedecomposition onset temperature was 317.4° C. A portion of this compoundwas mixed with 2% by weight dicumyl peroxide and this mixture wasanalyzed using a differential scanning calorimeter (DSC, ramp rate at10° C./minute, air purge). The catalyzed compound was found to cureonset of 129.4° C., a cure maxima of 137.8° C. and a cure energy of133.4 J/g.

Example 6 Synthesis of Compound 12

A 500 ml, two-neck flask was charged with 57.5 g (100 mmol) of Compound2 as a 50% solution in toluene, 8.9 g (50 mmol) Simulsol PTKE (SeppicUK, Ltd. Hounslow, England), and a magnetic stir bar. A temperaturecontroller, Dean-Stark trap, condenser, and bubbler were attached. Theflask was purged with argon and the mixture was then brought up toreflux at a pot temperature of 130° C. (once again, it was necessary toremove excess toluene in order to attain this temperature). Thiscondensation reaction was continued for three hours and 1.8 ml(equivalent to theory) of water was collected. The mixture was thencooled and the flask was charged with 61.5 g (200 mmol) of Compound 3,and 290 mg hydroquinone. This new mixture was then refluxed under air at130° C. for 92.25 hours. This second condensation step generated 3.5 mlwater (theory=3.6). The solution was cooled to room temperature, dilutedwith another 200 ml toluene and then passed over 25 g silica gel. Thetoluene was removed via rotary evaporation followed by air sparge. Theproduct was a very viscous, brown-black liquid that weighed 82.4 g(85.4% of theory). An FTIR trace on this liquid revealed significantabsorptions at 2926, 1732, 1641, 1414, 1161, 971, and 922 wavenumbers. ATGA was run on this compound (ramp rate at 10° C./minute, air purge) theresidual weight was 98.5% at 200° C. and 91.2% at 300° C. Thedecomposition onset temperature was 308.3° C. A portion of this compoundwas mixed with 2% by weight dicumyl peroxide and this mixture wasanalyzed via DSC (ramp rate at 10° C./minute, air purge). The catalyzedcompound was found to cure onset of 160.0° C., a cure maxima of 185.1°C. and a cure energy of 79.9 J/g.

1. A method for preparing a monomer, comprising reacting a substituted or unsubstituted bifunctional cyclic anhydride with a bifunctional amine according to the reaction Scheme A:

wherein: X is selected from the group consisting of a cycloaliphatic, an aromatic and a heteroaromatic moiety forming a condensed ring system with the furan ring of compound I; Y is absent or is selected from the group consisting of a C₁-C₁₅ alkyl and a C₂-C₁₅ alkylene moiety; and each of R₁ and R₂ is a moiety comprising a reactive functional group independently selected from the group consisting of hydroxyl, carboxyl, vinyl, allyl, acrylate and methacrylate, thereby obtaining the monomer II.
 2. The method of claim 1, wherein X is selected from the group consisting of cyclohexane and benzene.
 3. The method of claim 1, wherein Y is a C₂-C₁₅ alkylene moiety.
 4. The method of claim 1, wherein Y is a C₂-C₁₅ alkylene moiety dodecenyl group.
 5. The method of claim 1, wherein the cyclic anhydride is selected from the group consisting of succinic anhydride, isobenzofuran dione, hexahydro isobenzofuran dione, and derivatives thereof.
 6. The method of claim 1, wherein the bifunctional amine is selected from the group consisting of diethanolamine, dibutanolamine, and diallylamine.
 7. A method for preparing a hyperbranched polymer, comprising reacting the monomer II of claim 1 with a compound having a functionality selected from the group consisting of hydroxyl and carboxyl.
 8. A monomer produced by the process of claim
 1. 9. The monomer of claim 8, wherein the monomer selected from the group consisting of compounds 1, 3 and 4:


10. A hyperbranched polymer produced by the method of claim
 7. 11. The hyperbranched polymer of claim 10, wherein the hyperbranched polymer is selected from the group consisting of compounds 5, 6, 11 and 12:


12. A method for increasing toughness of an adhesive composition, comprising incorporating into the composition a hyperbranched polymer of claim
 10. 13. A composition comprising at least one hyperbranched polymer of claim
 10. 14. The composition of claim 13, wherein the composition is an adhesive composition.
 15. An adhesive composition of claim 14, further comprising a chain-extended bismaleimide and at least one compound selected from the group consisting of an epoxy, an oxetane, a phenol, a phenyl acetate, an acrylate, a methacrylate, a maleimide, a vinyl ether, a vinyl ester, a styrenic compound and an allyl functional compound.
 16. An adhesive composition comprising at least one hyperbranched polymer of claim
 11. 17. A composition comprising at least one hyperbranched polymer of claim
 8. 18. An adhesive composition comprising at least one monomer of claim
 9. 